UK Main Earth and Gas Bond

[Jonny72]

Folks need advice. House I am working on. TT earthing. The rod is closer to the gas pipe/meter box than the Consumer Unit. I wondered why I could find no bonding conductor in the CU. It appears someone took the Main Earth 16mm cable from the earth rod to the gas pipe and then onto the Consumer Unit. The cable is not broken and continuous. II can't see this being correct but can't establish where in Regs it's not compliant. Maybe I am too fussy as I like to see bonding conductor's on the MET not going hunting for them. Am I right, if so where in Regs?

 

[loz2754]

542.4 Main earthing terminals or bars.
542.4.2 "To facilitate measurement of the resistance of the earthing arrangements, means shall be provided in an accessible position for disconnecting the earthing conductor..."

To my mind, having the gas bonding incorporated in the earthing conductor does not provide for this regulation to be fulfilled, as disconnecting the earthing conductor at the DB would not disconnect it from the gas pipe, leading to erroneous measurements.

 

[Jonny72]

542.4 Main earthing terminals or bars.
542.4.2 "To facilitate measurement of the resistance of the earthing arrangements, means shall be provided in an accessible position for disconnecting the earthing conductor..."

To my mind, having the gas bonding incorporated in the earthing conductor does not provide for this regulation to be fulfilled, as disconnecting the earthing conductor at the DB would not disconnect it from the gas pipe, leading to erroneous measurements.

Excellent and prompt reply. Are you quoting this from recall If so I am impressed. Yes it did not feel right to be honest and often my gut reaction has been right.. Maybe I should rely on that a bit more. Obviously this has been done by the gas Installler a few years ago. I had looked through section 5 of the Regs but sometimes I find interpretation is everything. Totally agree with your assessment and will help greatly. Thankyou

 

[brianmoooore]

Possibly the original installer was confused by the fact that it is permissible to bond more than one service with the same unbroken cable.

 

[Mike Johnson]

One of these between the earth rod and gas main would allow disconnection from the CU and gas pipe: barrette de mesure terre - Recherche Google - https://www.google.com/search?

Is having to disconnect inside the DB an accessible position?

 

[Simon47]

Surely it's easy enough to just drop the wire off the clamp on the gas pipe during testing ?

 

[loz2754]

Surely it's easy enough to just drop the wire off the clamp on the gas pipe during testing ?

Indeed it would be. But that would mean having 2 things to disconnect instead of one. More margin for error. Of course, any diligent spark would pick up on this and just do what you said, but it seems against the intent of the reg quoted to have 2 things to disconnect.

 

[oscar21]

I've come across a similar scenario, TT system that has a rod outside and a 16mm earth going to the consumer unit as it should do, reading about 100 ohms. However the gas meter is close to the rod outside and someone has taken the gas bond to the rod and not the consumer unit. Would you pull this?

 

[Mike Johnson]

Sound like it needs one of these: P04350 | SIB Copper Earth Bar L. 78mm x W. 35mm x H. 46mm 5 Ways | RS - https://uk.rs-online.com/web/p/earth-bars/2705239

 

[Mike Johnson]

Another version:

 

[oscar21]

Are they classed as weatherproof earth terminals? At the minute its got a lug crimped onto the gas bond and its bolted to the rod along with the main earth, suppose you could come off the rod into that earth bar externally and then to the gas and consumer unit.
But would it make any difference at all to the way its done at the minute apart from making it a bit eaqsier to diconnect.